Memory devices are typically provided as internal, semiconductor, integrated circuits in computers or other electronic devices. Memory devices are utilized for a wide range of electronic applications such as personal computers, portable memory sticks, solid state drives (SSDs), digital cameras, cellular telephones, portable music players such as MP3 players, movie players, and other electronic devices. In addition to efforts to decrease the size of memory and memory devices, efforts are being made to increase the speed of communicating with memory and memory devices, and decrease the power consumption of memory and memory devices.
Various Serial Peripheral Interface (SPI) devices can be configured to receive/transmit data synchronously in a first transfer rate (1TR), e.g., a single transfer rate (STR), or a second transfer rate (2TR), e.g., double transfer rate (DTR). A SPI device in STR mode means that the device synchronously receives data on one edge of the clock, e.g., a rising edge, and synchronously transmits data on the other edge of the clock, e.g., a falling edge. A SPI device in Double Transfer Rate (DTR) mode means that the device synchronously receives and transmits data on both edges of the clock, e.g., rising and falling edges.
As SPI devices try to achieve higher DTR frequencies, and thus higher data communication rates, SPI devices may also be configured to enter a deep-power-down (DPD) mode in order to curtail power consumption when not communicating data. DPD mode is a lowest power consumption state for a device other than power down, e.g., off. DPD mode is a lower power consumption state than a standby mode, for example.